Name ______Date ______Block __

Circular Motion Review/Study Guide

Name / Radius Of Body
(x 106 m) / Mass
(Kg) / Average Orbital Radius
(x 1011 m)
Sun / 696 / 1.991 x 1030 / 0
Mercury / 2.43 / 3.2 x 1023 / 0.580
Earth / 6.3713 / 5.97 x 1024 / 1.4957
Mars / 3.40 / 6.42 x 1023 / 2.278

1.  What is circular motion?

2.  A car traveling 15m/s on a flat surface turns in a circle with a radius of 25m. What is the centripetal acceleration of the car?

3.  When a solid wheel rotates about a fixed axis, do all the points on the outside edge of the wheel have the same tangential speed?

4.  A young boy plays with a ball attached to the end of a 2.5m rope. He swings it around in a circle above his head. The ball has a tangential velocity of 5.23m/s. What is the balls period?

5.  What is tangential speed/acceleration?

6.  A building superintendent twirls a set of keys in a circle at the end of a cord. If the keys have a centripetal acceleration of 100 m/s2 and the cord has a length of .54m, what is the tangential speed of the keys?

7.  A test car moves at a constant speed around a circular track. If the car has a tangential speed of 19.7 m/s and an acceleration of 8.05 m/s2 what is the distance the car is from the center of the track?

8.  What is centripetal force? What is gravitational force?

9.  What is the difference between the two?

10.  Even though an object moving in a circle can have a constant speed(vt), can it still have an acceleration. How explain.

11.  A pilot is flying a small plane at 56.6m/s in a circular path with a radius of 188.5m. The centripetal force needed to maintain the plane’s circular motion is 18,900N. What is the plane’s mass?

12.  When an apple falls does the Earth accelerate up toward the apple?

13.  If the gravitational force between the electron (9.11x10-31 kg) and the proton (1.67 x 10-27kg) in a hydrogen atom is 1.0 x 10-47N, how far apart are the two particles?

14.  What is the distance between two 0.800kg billiard balls if the gravitational force between them is 8.92 x 10-11N?

15.  What is the gravitational force a 66.5 kg person would experience while standing on the surface of Mars

16.  A geosynchronous orbit places a satellite over one spot on the earth. These orbits all have a radius of 4.23 X 107 m. Compute the speed of such a satellite. Compute the period of the satellite.

17.  Compute the period of a satellite, which is in orbit 255km above the surface of Mercury.

18.  Compute the orbital speed of a satellite, which is in orbit 255km above the surface of Mercury.

19.  A tiny alien spaceship and the International Space Station are both orbiting Earth in circular orbits and at the same distance from Earth. Which one has a greater orbital speed?

20.  A sock stuck to the side of a clothes-dryer barrel has a centripetal acceleration of 28m/s2. If the dryer barrel has a radius of 27cm, what is the tangential speed of the sock?

21.  If a satellite orbiting Earth is in free fall, why does the satellite not fall and crash into Earth?

22.  How does the gravitational force exerted by Earth on the Sun compare with the gravitational force exerted by the Sun on the Earth?

23.  Would you expect tides to be higher at the equator or at the North Pole? Why?

24.  What is the difference between gravitational field strength and gravitational force?

25.  How does gravitational field strength change for an object the closer it gets to the center of a planet?

26.  What unit is gravitational field strength measured in?

27.  A new planet is discovered in a near by galaxy. It has a diameter of 4.776 x 1010 and a mass of 8.39 x 1031kg. Could we live there based on its gravitational field strength?

28.  If a newly discovered planet is discovered within the solar system. It is estimated to have a radius of 8.325 x 108m. Even more exciting, it has the same gravitational field strength at the surface as we have here on Earth. What is the mass of this planet?